Snowmobilers ride snow-covered trails last year in Mount Holly. The start of snowmobile season this year in Vermont is set for Dec. 16.

MONTPELIER — It’s December, winter is on the horizon and Vermont’s snowmobile season is set to open — if there’s enough snow.

Snowmobile clubs across the state are putting up signs, fixing bridges and trimming brush on the 4,700 miles of groomed corridor trails and 1,500 miles of less-well maintained feeder trails in anticipation of the Dec. 16 start.

Snowmobile season is legally timed to start after the last possible day of the fall deer hunting season and the December muzzleloader and archery seasons. They end Dec. 15.

In years when deer season ends earlier, trail groomers begin packing the trails in the days before the snowmobile season opens. Matt Tetreault, the trails administrator for the Vermont Association of Snow Travelers, which oversees snowmobiling across the state, said that can’t happen this year because snowmobilers want to respect the rights of hunters to be in the woods.

He said it could take several days after the end of hunting season before groomers have the opportunity to get the trails ready.

“We’re trying to get our message out there and respect our landowners and fellow sportsmen with the deer season,” he said. “We need to stay out of the woods until the 16th.”

About 24,000 people registered to use the trails last year, and Tetreault said his group is hoping to exceed that number this year.

While Vermont’s ski industry, which has extensive snowmaking systems, gets most of the attention, snowmobilers — dependent on natural snow — also add to the state’s economy.

In the past, VAST has estimated that snowmobiling contributes about $555 million in revenues to businesses across the state, including convenience stores, hotels, restaurants and gas stations that allow riders to drive their machines to the pumps.

VAST is branching out beyond snowmobile trails. The organization is administering a federal grant to upgrade portions of the 93-mile Lamoille Valley Rail Trail, which runs across northern Vermont from St. Johnsbury to Swanton.

This fall, two new bridges were built between Danville and St. Johnsbury, and VAST is seeking bids for construction of two more sections of trail.